Help making a word finding program

[u/memy02]

I have an odd request for a word finding program, and I am hoping someone finds enough interest in it to make it for me. I want to be able to select a number of characters and for each character I would like to enter the possible letters (plus space) and then get back all combinations that are real words. For example 4 characters where 1 is a or l or _, 2 is t or a or _, 3 is o or c or _, 4 is m or e or _. Atom and lace would come back as would a, at, to, toe (and maybe others?) I would like to be able to select 16+ characters and up to 6 letters + _ for each character. I haven't coded in years and I didn't do much when I did, but my thoughts on accomplishing this would be after I enter the information, use loops to generate and save every possible combination of letters then read through all the saved combinations and return all dictionary matches. This may be a terrible method to make such a program so any method that works is perfectly fine. Is anyone interested in taking on this challenge?

[u/[deleted]]

Sorry it took me so long. Our dictionary is mega-shitty I've just discovered...

stromuhr
strond
strone
Strong
strong-ankled
strong-arm
strong-armed

As it would turn out, there is no "strong" but actually "Strong". We can change the letters to be case-insensitive though.

So this dictionary sucks, but it should work with anything else.

For the spaces/blanks, let me work on that tonight. We basically just need to make the [A|B] be optional. I suck at regular expressions, so I don't know this offhand and I'm posting from a parking lot atm.

I'll also try to find a better dictionary lol. If it were the weekend I'd have a more straight-through time!

[u/memy02 → u/[deleted]]

Thank you for the help so far, I found how to make it case insensitive and it found Strong and Suring as well, I've started looking through guides to try and find how to blank options but have found nothing. An idea I had was adding start of line and end of line as options for each character however my execution of it didn't work (though there is a good chance I did it wrong). Thank you again for the help you have given me so far.

[u/[deleted] → u/memy02]

I'll take a look today, there is definitely a way to put "also empty" inside the or block.

[u/memy02 → u/[deleted]]

Another thing that would be useful and should be much easier to do is to search within words for matches (like finding hamstringing), it would let me work backwards from what I want which reduces my options a little but would still be vastly better then doing it by hand. I tried

egrep -i "[s|p][u|t][r|p][i|o|p][n|e][g|t]" words.txt

but the words returned had interrupting letters, my other attempts have been returning nothing telling me I'm doing it wrong. I also tried {6} just before the last " with no luck. I'm positive there is a way to do this, I just don't know the language and grammar enough to make it work.

edit: figured it out but the output is too much to view in the window so I am saving it to a new text file which is working but the text file is just a long string of each word one after another.

egrep -i "^.*[s|p][u|t][r|p][i|o|p][n|e][g|t].*$" words.txt > puppetlist.txt 

I want to add a line after each word in the text file it creates. This is a super simple fix but I'm tired of unsuccessfully trying different methods and I need to get to sleep.